Multiple clutches for motor vehicles are often classified by their type of friction partner as dry clutches or wet clutches, i.e., cooled by a liquid cooling medium. Multiple clutches, in particular double clutches, may also be classified by their arrangement. Particularly, in the case of wet double clutches, there is the radially nested design (“concentric arrangement”), in which the friction disks of a radial outer clutch, when brought into friction lock, surround the corresponding friction disks of a radial inner clutch, and the axially arranged series design, in which the friction disks of the clutches are arranged in series along a common axis of rotation (“parallel arrangement”).
A multiple clutch in parallel design is disclosed, for example, in document EP 1 195 537 A1. Multiple clutches in radially nested design, to which the invention relates, are described for example in EP 0 758 434 B1, DE 101 11 202 A1, DE 102 31 405 A1, DE 102 22 933 A1, DE 203 10 015 U1, DE 102 03 618 A1, DE 102 23 892 A1, DE 100 04 186 A1 or DE 100 04 189 A1.
The clutches proposed in these documents comprise a first clutch, below referred to as a radial outer multiple disk clutch, with an outer disk support supporting at least one outer disk and with an inner disk support supporting at least one inner disk, as well as a second clutch, below referred to as a radial inner multiple disk clutch, with an outer disk support supporting at least one outer disk and with an inner disk support supporting at least one inner disk. The disks of the radial outer multiple disk clutch and the disks of the radial inner multiple disk clutch rotate about a common axis of rotation. There, the disks of the radial outer multiple disk clutch are located radially outside the disks of the radial inner multiple disk clutch, while the disks of the radial outer multiple disk clutch and the disks of the radial inner multiple disk clutch are as a rule located in the same axial section, so that the disks of the radial outer multiple disk clutch reach radially around the disks of the radial inner multiple disk clutch. Each clutch comprises an actuating piston, by means of which the disks of the respective clutch can be brought into friction lock. Each actuating piston is guided axially displaceable by a corresponding cylinder. The cylinder and actuating piston in each instance form a so-called pressure chamber, which by means of a fluid, in particular a hydraulic fluid, can be acted on by a pressure, in order to bring the disks into (or out of) frictional engagement. Frequently, a so-called equalizing piston is in addition assigned to one or both actuating pistons. The actuating piston(s) and equalizing piston form a so-called equalizing chamber. This equalizing chamber may likewise be supplied or filled with a fluid, i.e., for example with hydraulic fluid. The fluid found in this equalizing chamber serves (largely) to equalize any superelevation of pressure in the pressure chamber due to centrifugal force occurring with increasing speed. In some cases, under- or overcompensation of this pressure superelevation may even be desirable.
The clutches proposed in the documents mentioned above are optimized with regard to a wide variety of parameters. Therefore, some of them differ considerably in the space they require for installation.
In most of the multiple clutches presented and described in the printed sources mentioned above, in particular double clutches, the individual disk supports are designed as separate structural parts. In the right-hand half of FIG. 1 of EP 0,758,434 B1, from which the invention starts out, there is shown a double clutch arrangement in radially nested design, in which the radial outer multiple disk clutch and the radial inner multiple disk clutch have a common disk support, which supports the outer disks of the radial inner multiple disk clutch and the inner disks of the radial outer multiple disk clutch. The common disk support thus results in double utilization, namely as inner disk support of the radial outer clutch and as outer disk support of the radial inner multiple disk clutch.
Both the outer disk support of the radial outer multiple disk clutch and the outer disk support of the radial inner multiple disk clutch support steel disks. The inner disk supports of both clutches support so-called friction disks, which are provided on both faces with a friction lining. For application of the counterforce to the respective disk package upon actuation of the clutches by the actuating piston assigned in each instance, endplates are provided, which close off or support the disk package on the side opposite to the respective actuating piston. These endplates are made of steel disks in both clutches, which are supported by the respective outer disk support and which are stop-limited by a safety ring.
Although each of the clutches has basically proven its worth for the respective application described in the above-mentioned printed sources, a need for improvement still exists.
The object of the invention, therefore, is to keep the space required for installation as small as possible, to keep the number of components necessary for making the clutch arrangement small and to make manufacture as simple as possible.